We are so totally in a fall state of mind. Mums have replaced geraniums in the terra cotta pots; apples have replaced peaches in the fruit bowl and -- okay, feeling a little guilty here -- the thought of putting together a holiday shopping list has at least crossed our mind. It's time to embrace this season when sweaters come out of hibernation and the idea of a fire crackling in the hearth seems so worth the effort. Speaking of worth the effort, here are the next three months of events in the Washington area that are so worth your putting them on your calendar now before you go back to cuddling the cat. Make sure to keep up with Weekend, Sunday Source, Style on the Go and Going Out Guide for other fun ideas.

September 6-7

Join in as a half-million people celebrate the rich traditions, strengths and cultures of the black family in this two-day festival featuring pavilions, health screenings and plenty of great food. On the Mall. A concert each night at 5:30 winds down the day’s activities. www.ncnw.org/events/reunion.htm. FREE

September 6-7

The saying goes that you’re either a cat person or a dog person. Well, apparently 38.4 million Americans are cat people. If you’re one of them, you won’t want to miss this cat show, with cats up for adoption, kittens for sale and the always-popular cat agility competition. Dulles Expo Center, 4368 Chantilly Shopping Center, Chantilly. Sept. 6 from 9:30 a.m. to 5 p.m. and Sept. 7 from 9:30 a.m. to 4 p.m. www.nationalcapitalcatshow.com. $8, age 11 and younger and age 60 and older $5. (Discount coupon online.)

September 13

The great thing about the Kennedy Center is that, thanks to its Millennium Stage concerts, it has an open house 365 days a year. But this special day-long celebration with the theme “American Stories, Songs and Steps” features dozens of FREE performances of music, dance and theater. Festivities start at noon at the Kennedy Center, 2700 F St. NW. www.kennedy-center.org.

September 13

Is it possible for a portrait to be both stark and glam? The work of photographer Richard Avedon, who shot coal miners, fashion models and more, often displays a mix of clinical dispassion and slickness. About 250 of the artist’s portraits (mainly boldface names, but also ordinary citizens caught up in late-20th-century politics) go on view at the Corcoran Gallery of Art through Jan. 25. At the Corcoran, 500 17th St. NW. www.corcoran.org. Admission to the exhibit, which includes the permanent collection, is $14; $12 for seniors and military; $10 for students; free for children younger than 6 and members.

September 21

Maybe you won’t be able to peek inside the medicine cabinets, but this once-a-year chance to see some of Embassy Row’s prime real estate is almost as good. The tour benefits the Woodrow Wilson House, a stop on the tour. Noon to 5 p.m. starting at the Wilson House, 2340 S St. NW. www.woodrowwilsonhouse.org. $25 in advance; $30 the day of the tour.

September 25

Have you been meaning to get out to the new stadium all summer long? Well, it’s your last chance as the Nats finish their home season against the Florida Marlins. Unless they make the playoffs, that is. Hey, we believe in our boys of summer. Nationals Park, 1500 South Capitol St. SE, at 7:10 p.m. www.washingtonnationals.com. Tickets start at $5.

September 27

The National Museum of Natural History unveils its biggest, most complex exhibition devoted to the planet’s biggest, most complex ecosystem: the ocean (it would be pretty silly to call it Ocean Hall if it wasn’t about oceans). The hall will feature a 45-foot-long North Atlantic right whale model, a 24-foot female giant squid and a 1,500-gallon coral reef tank with more than 70 live animals. National Museum of Natural History, 10th Street and Constitution Avenue NW. www.mnh.si.edu/exhibits/ocean%5Fhall. FREE

September 27

Man, the Mall is going to be crowded this day, with people checking out the new ocean exhibition at the National Museum of Natural History and more than 100,000 bibliophiles attending the Library of Congress’s annual book love-in. On the Mall between Third and Seventh streets. From 10 a.m. to 5 p.m. www.loc.gov/bookfest. FREE

Oct. 1-7

With a bit of a nip in the air, the fourth annual festival arrives just in time to heat things up. The weeklong celebration, named after Washington's native son, features performances throughout the city (think Kennedy Center, Blues Alley, Atlas Performing Arts Center) with genres including spoken word, Cubano and swing. There are performances from morning to night, and many are - here's that magic word - free, so there's no excuse for not catching at least one of these so-hot-they're-cool performances. For a complete schedule, with venues, performers and ticket prices, go to www.dejazzfest.org.

Oct. 10-12

One stop could take care of all your holiday gift needs at this showcase of hundreds of artists and artisans. There's entertainment value, too, including watching craftspeople, well, craft their wares. Montgomery County Fairgrounds, 16 Chestnut St., Gaithersburg. For other Sugarloaf festivals in the area and for ticket information, go to www.sugarloafcrafts.com. $7 online, $8 at door.

Opens Oct. 19

The National Gallery of Art opens its first exhibition devoted to ancient Roman art with more than 150 paintings, sculptures and mosaics. Get a sense of what it was like to live in the lap of luxury in the 1st century B.C., when prominent Romans would retreat to seaside homes in the shadow of Mount Vesuvius. The exhibition also features recent archaeological finds that have never been displayed in the United States. The exhibition continues through March 22. National Gallery of Art, between Third and Seventh streets at Constitution Avenue NW (Metro: Archives). www.nga.gov. FREE.

Oct. 30

Going through Olympics withdrawal? Yearning to see Nastia Liukin and Shawn Johnson flip, spin and tumble? Catch the athletes and former Olympic gymnasts as Team USA performs with some of Disney's top young musicians. 7:30 p.m. Verizon Center, Seventh and F streets NW (Metro: Gallery Place-Chinatown). www.ticketmaster.com. $29.50-$125.

Halloween

What would October be without a host of frightful, fun activities. Here are a few favorites that you may need to plan ahead for:

Oct. 23-26

The annual extravaganza to trick-or-treat among lions, tigers and bears is Oct. 23-26 from 5:30 to 8:30 p.m. National Zoo, 3001 Connecticut Ave. (Metro: Woodley Park-Adams Morgan or Cleveland Park; but the walk back to the Metro after trick-or-treating could mean carrying your little character.) nationalzoo.si.edu/Activitiesandevents. $25 age 2 and older

Oct. 19-Nov. 23

One of the city's most beautiful buildings becomes boo-tiful for nine evenings. For age 10 and older. Oct. 19, 24, 28 and Nov. 3, 16 and 23. National Building Museum, 401 F St. NW (Metro: Judiciary Square). www.nbm.org. $18.

Oct. 25

Paired with a 5K run for the slightly more serious, this event pairs the arts with healthy living. After crossing the finish line, enjoy a costume contest, theater performances and live music. Oct. 25. Wolf Trap Center for the Performing Arts, 1645 Trap Rd., Vienna. www.wolftrap.org. $10-$20 depending on event; family packages available.

Nov. 6-9

Knitting: It's not your grandma's hobby anymore. This four-day, knit-one, purl-two spectacular features classes, wool, patterns, equipment and mostly a chance for people who love the satisfaction of creating sweaters, scarves and afghans from balls of yarn to talk about new wool combinations and techniques. Seminars include "CSI: Cable Stitch Investigation" and "Focus on Sox." Baltimore Convention Center, 1 W. Pratt St., Baltimore. www.knittinguniverse.com. Registration required; $50-$625, depending on how many sessions you choose to attend.

Nov. 7

There is probably no more interesting face in American history than that of Abraham Lincoln. As part of events celebrating the 200th anniversary of his birth, the National Portrait Gallery will open an exhibition of more than 30 images of Lincoln, including the famous "tousled hair" portrait from 1857 and a Mathew Brady photograph that has been dubbed "the photograph that made Lincoln president." Through July 5. National Portrait Gallery, Eighth and F streets NW. www.npg.si.edu. FREE.

Nov. 15

Of course, any day could be Family Volunteer Day, but if you need a little push to get out there and do good, head to the parks in Howard County. Families, friends, scouts or religious groups can clean up and beautify parks and historical sites. Bring canned goods or paper products to benefit the Howard County Food Bank. Various sites throughout the county from 9 a.m. to noon. Call 410-313-4624 for more information or to sign up for a site. FREE, or as we like to say, priceless.

Nov. 15-22

Gallery exhibitions, lunchtime lectures and a photo contest are all part of a celebration of the art of photography for the first FotoWeek festival. There will be opportunities for aspiring photographers to learn, veteran photographers to exhibit their work and photo lovers to meet the artists with a unique eye on the world. Locations throughout the region, including Discovery Communications in Silver Spring, National Geographic and the Corcoran Gallery of Art as well as more than 40 galleries. www.fotoweekdc.org. Most events are FREE.

Nov. 21

Old Glory, we've missed you and all the other treasures that are part of what we affectionately know as "America's Attic." Closed for more than two years, the museum that is home to the first ladies' gowns, Julia Child's kitchen and Dorothy's ruby red slippers will be unrecognizable when it reopens. Walls of windows, skylights, open staircases and a special display case and exhibition room for that grand ol' flag that inspired the national anthem await a new generation of visitors. National Museum of American History, 14th Street and Constitution Avenue NW (Metro: Smithsonian, Federal Triangle). www.americanhistory.si.edu. FREE, so expect crowds.

Nov. 23-24

Man, is this Rock and Roll Hall of Famer still getting it done or what? The question isn't whether the eight-time Grammy winner, who incidentally will turn 70 next year, will amaze with a sexy, driving, sweaty show but rather how many of her iconic hits ("Proud Mary," "What's Love Got to Do With It?," "River Deep Mountain High") she'll pack into a performance. Sometimes, diva is a richly deserved compliment. 7 p.m. Verizon Center, Seventh and F streets NW (Metro: Gallery Place-Chinatown). www.ticketmaster.com. $59.50-$153.

Nov. 23

The theater celebrates its renovation with a family-friendly open house that will feature costume design workshops for kids, stage makeup lessons and demonstrations on how fight scenes are staged. There will also be performances, dance classes, poetry readings and improvisation workshops. Source, 1835 14th St. NW. (Metro: U Street/Cardozo/African American Civil War Memorial). www.sourcedc.org. FREE.

Nov. 27

So you really don't want to cook on this most American of holidays, but you feel really guilty because you and kith and kin should have a special holiday, right? You can do both if you reserve a spot at the historic Alexandria eatery that entertained the likes of Thomas Jefferson, John Adams and James Monroe. They certainly play up the history angle with lamp-lit tables, strolling players and waiters in period costumes. Expect turkey and the trimmings as well as roast beef and ham, homemade breads and two kinds of pie for dessert. Gadsby's Tavern, 138 N. Royal St., Alexandria. www.gadsbystavernrestaurant.com. $47; half-price for children 12 and younger

Dec. 2

Who cares if it took longer and cost more to build the visitor center than it took to build the Capitol itself? On the 145th anniversary of the completion of the Capitol Dome, the three-story, underground visitor center, with movie theaters, an exhibition hall, cafeteria and gift shops, will finally open. Gone will be the days of visitors waiting outside, in blistering August heat or blustery January cold, for a tour of where senators and representatives carry out the nation's business. Capitol Visitor Center, on the east side of the Capitol between the Capitol building and the Supreme Court. (Metro: Union Station) www.aoc.gov/cvc. FREE.

Dec. 4-6

This classic E.B. White tale of Louis the trumpeter swan who cannot make a sound gets a new musical retelling in a world premiere at the Kennedy Center's Eisenhower Theater. The production features music by Tony winner Jason Robert Brown, and the staging showcases an onstage solo trumpeter. Kennedy Center, 2700 F St. NW (Metro: Foggy Bottom-GWU, with free shuttles). www.kennedy-center.org. $18-$35.

Dec. 10-11

Kids, poetry and the lilting beauty of the Spanish language come together in this two-day event sponsored by Teatro de la Luna. The marathon for elementary-school-age children is Dec. 10 from 10 to noon; middle- and high-schoolers get their chance at the same time Dec. 11. The readings are at the Martin Luther King Jr. Memorial Public Library, 901 G St. NW. For more information or to register a child (spaces fill up quickly), go to www.teatrodelaluna.org, and click on "9th Young People's Poetry Marathon" on the right. FREE.

Dec. 15-Jan. 17

This vibrant, unforgettable, revolutionary musical gets an unprecedented staging during its five-week run at the National Theatre before heading to Broadway. The cast of 37 Sharks, Jets and would-be peacemakers will feature Spanish in songs and dialogue. It's only fitting that the unique staging takes place at the National Theatre, where the play was first performed in 1957 before moving to Broadway. National Theatre, 1321 Pennsylvania Ave. NW. (Metro: Metro Center, Federal Triangle) www.nationaltheatre.org. $46.50-$151.50

Look for Weekend's special Holiday Happenings issue, with information on holiday light displays, Hanukkah events and more, on Nov. 28. And because we know just about everyone likes a sneak peek at what they're getting for the holidays, here's our early gift to you.

Dec. 4

Okay, so remember you heard it here first. It's really just fine to catch this on the 11 p.m. news, but if you want to go to say that you've been there, the president will flick the switch to illuminate an enormous tree Dec. 4. Details on how to get tickets will be available closer to the event at www.nps.gov/whho/national_christmas_tree_program.htm. FREE.

Nov. 29 through Dec. 27

The 120-voice choir sings holiday songs each Thursday, Friday and Saturday evening Nov. 29 through Dec. 27 on the plaza at the National Harbor in Prince George's County. www.nationalharbor.com/experience/entertainment/calendar.aspx. FREE.

Dec. 7

This holiday tradition marks its 40th anniversary with the Marine Band and a 400-voice choir leading the Washington area in song. The performance, which of course includes bell-ringing so don't forget to bring yours, begins at 4 p.m. at Wolf Trap's Filene Center on Dec. 7. Doors open at 3 p.m., and you're encouraged to arrive early. Wolf Trap Center for the Performing Arts, 1645 Trap Rd., Vienna. www.wolftrap.org. FREE; donations of new unwrapped toys will be accepted.

Dec. 4-6

This Alexandria holiday tradition features a children's tea party, tour of decorated homes and a parade of kilt-clad bagpipers, Scottish dancers, Scottish terriers and Santa Claus. Bundle up and go. Dec. 4-6. Go to www.scottishchristmaswalk.com for schedule of events and ticket information.